Efficient video workflow without multiple renders?
You can do most color correction with Strip modifiers. And if you don't need 3D effects for your text, you can use Text Strips in the VSE.

There are also addons to send strips to the compositor, but it should be better to avoid them if possible.

Finally you can import your video a second time and just delete the image part of it only keeping the audio strips to solve your last problem.

You should watch the YouTube videos from Mikeycal Meyers to get a better understanding of editing videos with the VSE.